S. Abbott (1), J. Hellewell (1), J. D. Munday (1), J. Y. Chun, R. N. Thompson (1), N. Bosse (1), Y. D. Chan (1), T. W. Russell (1), C. I. Jarvis (1), CMMID COVID team (1), S. Flasche (1), A. J. Kucharski (1), R. M. Eggo (1), S. Funk (1).

Correspondence to:

1. Center for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London WC1E 7HT, United Kingdom

Last Updated: 2020-03-17

Note: this is preliminary analysis, has not yet been peer-reviewed and is updated daily as new data becomes available. This work is licensed under a Creative Commons Attribution 4.0 International License. A summary of this report can be downloaded here

Summary

Aim: To identify changes in the reproduction number, rate of spread, and doubling time during the course of the COVID-19 outbreak whilst accounting for potential biases due to delays in case reporting.

Latest estimates as of the 2020-03-17

Global map


Figure 1: Global map of the expected change in daily cases based on data from the 2020-03-17. Note: only country level estimates are shown.

Summary of latest reproduction number and case count estimates


Figure 2: Cases with date of onset on the day of report generation and the time-varying estimate of the effective reproduction number (bar = 95% credible interval) based on data from the 2020-03-17. Countries/Regions are ordered by the number of expected daily cases and shaded based on the expected change in daily cases. The dotted line indicates the target value of 1 for the effective reproduction no. required for control and a single case required fror elimination.

Reproduction numbers over time in the six countries with the most cases currently


Figure 3: Time-varying estimate of the effective reproduction number (light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range) based on data from the 2020-03-17 in the countries/regions expected to have the highest number of incident cases. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence. The dotted line indicates the target value of 1 for the effective reproduction no. required for control.

Latest estimates summary table

Country/Region Cases with date of onset on the day of report generation Expected change in daily cases Effective reproduction no. Doubling time (days)
Italy 877 – 6291 Increasing 1 – 1.9 2.9 – Cases decreasing
United States 627 – 4790 Increasing 1.8 – 5.1 0.84 – Cases decreasing
Iran 579 – 4526 Increasing 1 – 1.9 2.7 – Cases decreasing
Spain 417 – 3046 Increasing 1.1 – 2.7 1.7 – Cases decreasing
France 348 – 2645 Increasing 1.1 – 2.5 1.9 – Cases decreasing
Germany 503 – 2297 Increasing 1.5 – 3.2 2.1 – 25
Switzerland 254 – 1968 Increasing 1.3 – 3.8 0.26 – Cases decreasing
Belgium 159 – 1004 Increasing 1.3 – 4.3 0.21 – Cases decreasing
Malaysia 108 – 700 Increasing 2.8 – 8.8 0.23 – Cases decreasing
Netherlands 84 – 668 Increasing 1.1 – 2.7 0.73 – Cases decreasing
Austria 43 – 383 Increasing 1 – 2.6 0.24 – Cases decreasing
United Kingdom 38 – 372 Increasing 1 – 2.4 0.27 – Cases decreasing
Canada 38 – 297 Increasing 1.6 – 4.7 1.6 – Cases decreasing
Greece 43 – 292 Increasing 1.4 – 5.2 0.18 – Cases decreasing
Portugal 35 – 256 Increasing 1.3 – 5.3 0.18 – Cases decreasing
Australia 29 – 245 Increasing 1.3 – 4.5 0.77 – Cases decreasing
Czechia 30 – 234 Increasing 1.1 – 3.5 0.17 – Cases decreasing
Norway 21 – 210 Likely increasing 0.9 – 2.1 0.44 – Cases decreasing
Iceland 30 – 208 Increasing 1.3 – 5.2 0.15 – Cases decreasing
South Korea 22 – 181 Unsure 0.6 – 1.3 32 – Cases decreasing
Denmark 18 – 179 Unsure 0.6 – 1.6 0.15 – Cases decreasing
Sweden 13 – 164 Unsure 0.7 – 1.6 0.59 – Cases decreasing
Israel 19 – 160 Increasing 1.1 – 3.6 0.16 – Cases decreasing
Philippines 18 – 150 Increasing 1.2 – 4 0.15 – Cases decreasing
Ireland 13 – 139 Increasing 1.2 – 3.8 0.18 – Cases decreasing
Qatar 11 – 114 Likely increasing 0.8 – 2.3 0.15 – Cases decreasing
Slovenia 7 – 100 Increasing 1 – 3.2 0.17 – Cases decreasing
Brazil 7 – 97 Increasing 1.1 – 3.6 0.17 – Cases decreasing
China 8 – 90 Unsure 0.6 – 1.2 3 – Cases decreasing
Singapore 7 – 69 Increasing 1.1 – 2.3 2.3 – Cases decreasing
China Excluding Hubei 3 – 64 Increasing 1 – 2.1 2.3 – Cases decreasing
Japan 1 – 50 Likely decreasing 0.7 – 1.1 18 – Cases decreasing
Bahrain 1 – 36 Likely decreasing 0.4 – 1.2 0.15 – Cases decreasing
Hubei 1 – 31 Decreasing 0.1 – 0.3 3 – Cases decreasing
Hong Kong 1 – 30 Likely increasing 0.7 – 2.4 0.22 – Cases decreasing
Finland 1 – 29 Likely increasing 0.9 – 2.5 0.18 – Cases decreasing


Table 1: Latest estimates of the number of cases by date of onset, the effective reproduction number, and the doubling time for the 2020-03-17 in each region included in the analysis. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate. China excludes Hubei.

Methods

Summary

Limitations

Detail

Data

We used partial line-lists from each region that contained the date of symptom onset, date of confirmation and import status (imported or local) for each case [3] where available. The region reports give details of the steps taken where this data were not available. Daily case counts by date of report were extracted from the World Health Organization (WHO) situation reports for every location considered [1,2]. The case counts (and partial line-lists where available) were used to assemble the daily number of local and imported cases. Where the partial line-lists and case counts disagreed, it was assumed that the partial line-lists were correct and the WHO case counts were adjusted so that the overall number of cases occurring remained the same but the number of local cases being adjusted as needed.

Adjusting for reporting delays

Reporting delays for each country were estimated using the corresponding partial line-list of cases. The reporting delay could not be estimated from line-list data for all regions. Region specific details are given in the individual regional reports. The estimated reporting delay was assumed to remain constant over time in each location. We fitted an exponential distribution adjusted for censoring [8] to the observed delays using stan [9]. We then took 1000 samples from the posterior distribution of the rate parameter for the exponential delay distribution and constructed a distribution of possible onset dates for each case based on their reporting date. To prevent spuriously long reporting delays, we re-sampled delays that were greater than the maximum observed delay in the observed data.

To account for censoring, i.e. cases that have not yet been confirmed but will show up in the data at a later time, we randomly sampled the true number of cases (including those not yet confirmed) assuming that the reported number of cases is drawn from a binomial distribution, where each case has independent probability \(p_i\) of having been confirmed, \(i\) is the number of days of the symptom onset before the report maximum observed report delay, and \(p_i\) is the cumulative distribution of cases that are confirmed by day \(i\) after they develop symptoms. We did not account for potential reporting biases that might occur due to changes in the growth rate of the outbreak over time.

Statistical analysis

We used the inferred number of cases to estimate the reproduction number on each day using the EpiEstim R package [5]. This uses a combination of the serial interval distribution and the number of observed cases to estimate the reproduction number at each time point [11,12], which were then smoothed using a 7-day time window. We assumed that the serial interval was uncertain with a mean of 4.7 days (95% CrI: 3.7, 6.0) and a standard deviation of 2.9 days (95% CrI: 1.9, 4.9) [7]. We used a common prior for the reproduction number with mean 2.6 and a standard deviation of 2 (inflated from 0.5 found in the reference) [13]. Where data was available, we used EpiEstim to adjust for imported cases [6]. The expected change in daily cases was defined using the proportion of samples with a reproduction number less than 1 (subcritical). It was assumed that if less than 5% of samples were subcritical then an increase in cases was definite, if less than 20% of samples were subcritical then an increase in cases was likely, if more than 80% of samples were subcritical then a decrease in cases was likely and if more than 95% of samples were subcritical then a decrease in cases was definite. For countries/regions with between 20% and 80% of samples being subcritical we could not make a statement about the likely change in cases (defined as unsure).

We estimated the rate of spread (\(r\)) using linear regression with time as the only exposure and logged cases as the outcome for the overall course of the outbreak [14]. The adjusted R^2 value was then used to assess the goodness of fit. In order to account for potential changes in the rate of spread over the course of the outbreak we used a 7-day sliding window to produce time-varying estimates of the rate of spread and the adjusted R^2. The doubling time was then estimated using \(\text{ln}(2) \frac{1}{r}\) for each estimate of the rate of spread.

We report the 95% confidence intervals for all measures using the 2.5% and 97.5% quantiles. The analysis was conducted independently for all regions and is updated daily as new data becomes available. Confidence in our estimates is shown using the proportion of data that were derived using binomial upscaling. Code and results from this analysis can be found here and here.

Regional reports

Italy

Summary


Figure 4: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 877 – 6291
Expected change in daily cases Increasing
Effective reproduction no. 1 – 1.9
Rate of spread -0.018 – 0.24
Doubling time (days) 2.9 – Cases decreasing
Adjusted R-squared -0.12 – 0.99


Table 4: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 5: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

United States

Summary


Figure 7: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 627 – 4790
Expected change in daily cases Increasing
Effective reproduction no. 1.8 – 5.1
Rate of spread -3.8 – 0.83
Doubling time (days) 0.84 – Cases decreasing
Adjusted R-squared -0.2 – 0.83


Table 5: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 8: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Iran

Summary


Figure 10: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 579 – 4526
Expected change in daily cases Increasing
Effective reproduction no. 1 – 1.9
Rate of spread -0.03 – 0.26
Doubling time (days) 2.7 – Cases decreasing
Adjusted R-squared -0.16 – 0.98


Table 6: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 11: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Spain

Summary


Figure 13: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 417 – 3046
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 2.7
Rate of spread -0.1 – 0.4
Doubling time (days) 1.7 – Cases decreasing
Adjusted R-squared -0.16 – 0.99


Table 7: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 14: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

France

Summary


Figure 16: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 348 – 2645
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 2.5
Rate of spread -0.064 – 0.37
Doubling time (days) 1.9 – Cases decreasing
Adjusted R-squared -0.16 – 0.98


Table 8: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 17: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Germany

Summary


Figure 19: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 503 – 2297
Expected change in daily cases Increasing
Effective reproduction no. 1.5 – 3.2
Rate of spread 0.027 – 0.33
Doubling time (days) 2.1 – 25
Adjusted R-squared 0.058 – 0.95


Table 9: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 20: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Switzerland

Summary


Figure 22: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 254 – 1968
Expected change in daily cases Increasing
Effective reproduction no. 1.3 – 3.8
Rate of spread -0.37 – 2.6
Doubling time (days) 0.26 – Cases decreasing
Adjusted R-squared -0.17 – 0.94


Table 10: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 23: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Belgium

Summary


Figure 25: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 159 – 1004
Expected change in daily cases Increasing
Effective reproduction no. 1.3 – 4.3
Rate of spread -0.21 – 3.4
Doubling time (days) 0.21 – Cases decreasing
Adjusted R-squared -0.17 – 0.92


Table 11: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 26: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Malaysia

Summary


Figure 28: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 108 – 700
Expected change in daily cases Increasing
Effective reproduction no. 2.8 – 8.8
Rate of spread -0.0023 – 3
Doubling time (days) 0.23 – Cases decreasing
Adjusted R-squared -0.088 – 0.94


Table 12: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 29: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Netherlands

Summary


Figure 31: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 84 – 668
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 2.7
Rate of spread -0.082 – 0.95
Doubling time (days) 0.73 – Cases decreasing
Adjusted R-squared -0.17 – 0.98


Table 13: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 32: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Austria

Summary


Figure 34: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 43 – 383
Expected change in daily cases Increasing
Effective reproduction no. 1 – 2.6
Rate of spread -0.15 – 2.9
Doubling time (days) 0.24 – Cases decreasing
Adjusted R-squared -0.16 – 0.96


Table 14: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 35: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

United Kingdom

Summary


Figure 37: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 38 – 372
Expected change in daily cases Increasing
Effective reproduction no. 1 – 2.4
Rate of spread -0.094 – 2.5
Doubling time (days) 0.27 – Cases decreasing
Adjusted R-squared -0.16 – 0.98


Table 15: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 38: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Canada

Summary


Figure 40: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 38 – 297
Expected change in daily cases Increasing
Effective reproduction no. 1.6 – 4.7
Rate of spread -0.054 – 0.43
Doubling time (days) 1.6 – Cases decreasing
Adjusted R-squared -0.19 – 0.98


Table 16: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 41: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Greece

Summary


Figure 43: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 43 – 292
Expected change in daily cases Increasing
Effective reproduction no. 1.4 – 5.2
Rate of spread -2.5 – 3.8
Doubling time (days) 0.18 – Cases decreasing
Adjusted R-squared -0.17 – 0.79


Table 17: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 44: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Portugal

Summary


Figure 46: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 35 – 256
Expected change in daily cases Increasing
Effective reproduction no. 1.3 – 5.3
Rate of spread -2.3 – 3.9
Doubling time (days) 0.18 – Cases decreasing
Adjusted R-squared -0.18 – 0.86


Table 18: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 47: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Australia

Summary


Figure 49: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 29 – 245
Expected change in daily cases Increasing
Effective reproduction no. 1.3 – 4.5
Rate of spread -0.21 – 0.9
Doubling time (days) 0.77 – Cases decreasing
Adjusted R-squared -0.17 – 0.89


Table 19: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 50: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Czechia

Summary


Figure 52: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 30 – 234
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 3.5
Rate of spread -0.19 – 4.1
Doubling time (days) 0.17 – Cases decreasing
Adjusted R-squared -0.16 – 0.96


Table 20: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 53: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Norway

Summary


Figure 55: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 21 – 210
Expected change in daily cases Likely increasing
Effective reproduction no. 0.9 – 2.1
Rate of spread -0.23 – 1.6
Doubling time (days) 0.44 – Cases decreasing
Adjusted R-squared -0.17 – 0.94


Table 21: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 56: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Iceland

Summary


Figure 58: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 30 – 208
Expected change in daily cases Increasing
Effective reproduction no. 1.3 – 5.2
Rate of spread -4.2 – 4.6
Doubling time (days) 0.15 – Cases decreasing
Adjusted R-squared -0.19 – 0.7


Table 22: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 59: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

South Korea

Summary


Figure 61: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 22 – 181
Expected change in daily cases Unsure
Effective reproduction no. 0.6 – 1.3
Rate of spread -0.22 – 0.022
Doubling time (days) 32 – Cases decreasing
Adjusted R-squared -0.15 – 0.93


Table 23: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 62: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Denmark

Summary


Figure 64: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 18 – 179
Expected change in daily cases Unsure
Effective reproduction no. 0.6 – 1.6
Rate of spread -0.39 – 4.7
Doubling time (days) 0.15 – Cases decreasing
Adjusted R-squared -0.28 – 0.87


Table 24: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 65: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Sweden

Summary


Figure 67: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 13 – 164
Expected change in daily cases Unsure
Effective reproduction no. 0.7 – 1.6
Rate of spread -0.27 – 1.2
Doubling time (days) 0.59 – Cases decreasing
Adjusted R-squared -0.15 – 0.97


Table 25: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 68: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Israel

Summary


Figure 70: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 19 – 160
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 3.6
Rate of spread -1.7 – 4.5
Doubling time (days) 0.16 – Cases decreasing
Adjusted R-squared -0.2 – 0.76


Table 26: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 71: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Philippines

Summary


Figure 73: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 18 – 150
Expected change in daily cases Increasing
Effective reproduction no. 1.2 – 4
Rate of spread -1.3 – 4.7
Doubling time (days) 0.15 – Cases decreasing
Adjusted R-squared -0.24 – 0.89


Table 27: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 74: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Ireland

Summary


Figure 76: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 13 – 139
Expected change in daily cases Increasing
Effective reproduction no. 1.2 – 3.8
Rate of spread -0.54 – 3.8
Doubling time (days) 0.18 – Cases decreasing
Adjusted R-squared -0.17 – 0.93


Table 28: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 77: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Qatar

Summary


Figure 79: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 11 – 114
Expected change in daily cases Likely increasing
Effective reproduction no. 0.8 – 2.3
Rate of spread -2.1 – 4.6
Doubling time (days) 0.15 – Cases decreasing
Adjusted R-squared -0.25 – 0.69


Table 29: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 80: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Slovenia

Summary


Figure 82: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 7 – 100
Expected change in daily cases Increasing
Effective reproduction no. 1 – 3.2
Rate of spread -1.8 – 4.1
Doubling time (days) 0.17 – Cases decreasing
Adjusted R-squared -0.28 – 0.84


Table 30: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 83: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Brazil

Summary


Figure 85: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 7 – 97
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 3.6
Rate of spread -0.66 – 4.2
Doubling time (days) 0.17 – Cases decreasing
Adjusted R-squared -0.18 – 0.92


Table 31: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 86: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

China

Summary


Figure 88: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 8 – 90
Expected change in daily cases Unsure
Effective reproduction no. 0.6 – 1.2
Rate of spread -0.16 – 0.23
Doubling time (days) 3 – Cases decreasing
Adjusted R-squared -0.24 – 0.66


Table 32: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 89: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Singapore

Summary


Figure 91: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 7 – 69
Expected change in daily cases Increasing
Effective reproduction no. 1.1 – 2.3
Rate of spread -0.074 – 0.3
Doubling time (days) 2.3 – Cases decreasing
Adjusted R-squared -0.16 – 0.77


Table 33: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 92: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

China Excluding Hubei

Summary


Figure 94: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 3 – 64
Expected change in daily cases Increasing
Effective reproduction no. 1 – 2.1
Rate of spread -0.17 – 0.31
Doubling time (days) 2.3 – Cases decreasing
Adjusted R-squared -0.17 – 0.76


Table 34: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 95: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Japan

Summary


Figure 97: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 1 – 50
Expected change in daily cases Likely decreasing
Effective reproduction no. 0.7 – 1.1
Rate of spread -0.44 – 0.039
Doubling time (days) 18 – Cases decreasing
Adjusted R-squared -0.16 – 0.78


Table 35: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 98: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Bahrain

Summary


Figure 100: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 1 – 36
Expected change in daily cases Likely decreasing
Effective reproduction no. 0.4 – 1.2
Rate of spread -1.6 – 4.6
Doubling time (days) 0.15 – Cases decreasing
Adjusted R-squared -0.21 – 0.82


Table 36: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 101: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Hubei

Summary


Figure 103: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 1 – 31
Expected change in daily cases Decreasing
Effective reproduction no. 0.1 – 0.3
Rate of spread -4.3 – 0.23
Doubling time (days) 3 – Cases decreasing
Adjusted R-squared -0.15 – 0.88


Table 37: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 104: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Hong Kong

Summary


Figure 106: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 1 – 30
Expected change in daily cases Likely increasing
Effective reproduction no. 0.7 – 2.4
Rate of spread -2.8 – 3.2
Doubling time (days) 0.22 – Cases decreasing
Adjusted R-squared -0.17 – 0.59


Table 38: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 107: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Finland

Summary


Figure 109: A.) Cases by date of report (bars) and estimated cases by date of onset. B.) Time-varying estimate of the effective reproduction number. Light grey ribbon = 95% credible interval. Dark grey ribbon = the interquartile range. Based on data from the 2020-03-17. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Estimate
Cases with date of onset on the day of report generation 1 – 29
Expected change in daily cases Likely increasing
Effective reproduction no. 0.9 – 2.5
Rate of spread -1.4 – 3.8
Doubling time (days) 0.18 – Cases decreasing
Adjusted R-squared -0.18 – 0.82


Table 39: Latest estimates of the number of cases by date of onset, the expected change in daily cases, the effective reproduction number, the rate of spread, the doubling time, and the adjusted R-squared of the exponential fit for the 2020-03-17. Based on the last 7 days of data. The 95% credible interval is shown for each numeric estimate.

Time-varying rate of spread and doubling time


Figure 110: A.) Time-varying estimate of the rate of spread, B.) Time-varying estimate of the doubling time in days (note that when the rate of spread is negative the doubling time is assumed to be infinite), C.) The adjusted R-squared estimates indicating the goodness of fit of the exponential regression model (with values closer to 1 indicating a better fit). Based on data from the 2020-03-17. Light grey ribbon = 95% credible interval; dark grey ribbon = the interquartile range. Confidence in the estimated values is indicated by shading with reduced shading corresponding to reduced confidence.

Implementation details

Updates

2020-03-18

2020-03-17

2020-03-14

2020-03-11

2020-03-07

References

1 World Health Organization. Coronavirus disease (COVID-2019) situation reports. https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports

2 Brown E. Data2019nCoV: Data on the covid-19 outbreak. 2020.

3 Xu B, Gutierrez B, Hill S et al. Epidemiological Data from the nCoV-2019 Outbreak: Early Descriptions from Publicly Available Data. 2020.

4 Abbott S, Hellewell J, Munday JD et al. NCoVUtils: Utility functions for the 2019-ncov outbreak. - 2020;-:–. doi:10.5281/zenodo.3635417

5 Cori A. EpiEstim: Estimate time varying reproduction numbers from epidemic curves. 2019. https://CRAN.R-project.org/package=EpiEstim

6 Thompson R, Stockwin J, Gaalen R van et al. Improved inference of time-varying reproduction numbers during infectious disease outbreaks. Epidemics 2019;29:100356. doi:https://doi.org/10.1016/j.epidem.2019.100356

7 Nishiura H, Linton NM, Akhmetzhanov AR. Serial interval of novel coronavirus (2019-nCoV) infections. medRxiv Published Online First: 2020. doi:10.1101/2020.02.03.20019497

8 Thompson RN. 2019-20 Wuhan coronavirus outbreak: Intense surveillance is vital for preventing sustained transmission in new locations. bioRxiv 2020;1–14.

9 Stan Development Team. RStan: The R interface to Stan. 2020.http://mc-stan.org/

10 R Core Team. R: A language and environment for statistical computing. Vienna, Austria:: R Foundation for Statistical Computing 2019. https://www.R-project.org/

11 Cori A, Ferguson NM, Fraser C et al. A New Framework and Software to Estimate Time-Varying Reproduction Numbers During Epidemics. American Journal of Epidemiology 2013;178:1505–12. doi:10.1093/aje/kwt133

12 Wallinga J, Teunis P. Different Epidemic Curves for Severe Acute Respiratory Syndrome Reveal Similar Impacts of Control Measures. American Journal of Epidemiology 2004;160:509–16. doi:10.1093/aje/kwh255

14 Park SW, Champredon D, Weitz JS et al. A practical generation-interval-based approach to inferring the strength of epidemics from their speed. Epidemics 2019;27:12–8. doi:https://doi.org/10.1016/j.epidem.2018.12.002